Plastic case for transporting packaged fresh milk



1955 A. w. KNIERIEM ET AL 3 9 PLASTIC CASE FOR TRANSPORTING PACKAGED FRESH MILK 3 Sheets-Sheet 1 Filed Sept. 20, 1954 p fl' 21 IN VEN TORS.

Dec. 11, 1956 A. w. KNIERIEM ET AL PLASTIC CASE FOR TRANSPORTING PACKAGED FRESH MILK 3 Sheets-Sheet 2 Filed Sept. 20, 1954 ARLINGTON W HN/EE/EM, Lou/5 Co $51.57;

IN VEN TORS.

Dec. 11, 1956 A. w. KNIERIEM ET AL 1 73,624

PLASTIC CASE FOR TRANSPORTING PACKAGED FRESH MILK Filed Sept. 20, 195.4

3 Sheets-Sheet 3 INVENTOR5.

Lou/s 0 1 01. $7;

AeLl/varolv BAUER/Ely),

ATTORNEY- United States i PLASTIC CASE FOR TRANSPORTING PACKAGED FRESH MILK Arlington W. Knieriem, Pasadena, and Louis C. Folst, Los Angeles, Calif., assignors to Calresin Industries, Inc., Los Angeles, Calif., a corporation of California Application September 20, 1954, Serial No. 457,008

3 Claims. (Cl. 220-97) This invention relates to the transporting of fresh milk packed in rectangular waxed paper cartons and particularly to a novel case for carrying a multiplicity of said cartons.

Milk must be kept constantly refrigerated while .being stored and transported incidental to its distributionto the retailer. Wooden crates, in which the milk cartons are temporarily packed, have heretofore been commonly used in this refrigerated handling and storage of packaged milk. Due to the high humidity prevalent in refrigerated trucks and storage rooms, these wooden crates, called milk cases absorb large quantities of moisture. causes the wood to swell and makes it necessary for the crate to be metal bound which makes the crates relatively heavy. The moisture so absorbed also adds to the crates weight to an extent which substantially increases the cost of handling and transportation of these wooden crates.

It is an object of the present invention to provide a novel case for use in handling fresh milk packaged in cartons which case will be substantially lighter than a This metal bound wooden crate and substantially inpervious to moisture. v

Another object is to provide a novel case of molded plastic construction having thin walls with spaced integral reinforcing elements which are so related to each other as to comprise a rigid skeletonal structure, yet which fit into a mold pattern allowing the case to be produced in g and withdrawn from a two part mold, and provide nesting formations at the upper and lower peripheral surfaces of said case which do not extend respectively above or below said surfaces.

The manner of accomplishing the foregoing objects as well as further objects and advantages will be made manifest in the following description taken in connection with the accompanying drawings in which:

Fig. l is a perspective view of a preferred embodiment of the invention.

Fig. 2 is a side elevational view of the invention partially I broken away to disclose the sectional construction of an end and adjacent bottom portion of the case.

Fig. 3 is an end elevational view of the invention partially broken away to show in section a side and adjacent bottom portion of the case.

Fig. 4 is a plan view of the invention.

Fig. 5 is a partial bottom plan view of the invention.

Fig. 6 is an enlarged fragmentary horizontal sectional side pilaster like integral reinforcing element.

Fig. 7 is a similar sectional view taken on the line 77 of Fig. 2 and shows a corner reinforcing element.

Fig. 8 is an enlarged fragmentary sectional view of an end wall of the case taken on the line 8-8 of Fig. 3. I Fig. 9 is an enlarged fragmentary sectional view of a bottom portion of a side wall of the invention taken on the line 9-9 of Fig. 2.

Fig. 10 is a perspective view showing three cases, em 'bodying the invention, stacked in nesting relation.

- view taken on the line 6-6 of Fig, 2, and showing a mid- 2,773,624 Patented Dec. 1 1, 1956 Fig. 11 is an enlarged detail sectional view taken on line 11- -11 of Fig. 10 and illustrating the manner in which upper and lower end portions of adjacent cases in a stack nest together.

Referring specifically to the drawings, the invention is therein illustrated as embodied in a plastic case 15 which, because of its unique design, is adapted to be made in a two part mold and also have the other characteristics heretofore mentioned.

The male and female halves of the mold (not shown) form the inner and outer surfaces respectively of the case 15, and the parting line between said mold halves is the outer boundary line of the top horizontal surface 16 of the case 15. All exterior surfaces of the case 15 are tapered downwardly from surface 16 so that case 15 will draw upwardly from the female half of the mold. Like-' wise,all internal surfaces of the case 15 are tapered downwardly to permit the case 15 to draw from the male half of the mold.

These limiting requirements had to be met in the development of the present invention. Thus, before the other objects of the invention could be realized and an internal carton carrying cavity provided meeting the existing space requirements, which of course could not be altered, the taper angles on some surfaces of the case 15 were reduced to the limit of what is generally considered good practice in plastic moulding.

The case 15 comprises a thin shell 17 having a reinforcing skeleton 18 formed integral therewith.

The shell 17 includes a bottom 19, having drainage perforations 20 formed therein, side walls 21, and end walls 22, the latter preferably having hand-holes 23 provided near their upper edge.

The shell 17 has a uniform thickness of .09" where not integrally united with the skeleton 18. The shell provides a clean surfaced approximately rectangular cavity 24 for accommodating either 24 quart milk cartons or 12 half gallon milk cartons. Each case, when loaded, thus'carries forty eight pounds of milk.

The downward taper between the side walls 21, and

between the end walls 22, is approximately forty-five minutes.

The side and end wall may be considered as extending downwardly about one-half inch below the bottom 19 to make it about 10%" from the top surface 16 of case 15 to bottom surface 25 of the case.

The exterior surfaces of side walls 21 and end walls 22 are clean of encumbrance below the level of the bottom 19 and because of the downward taper of said walls, the lower half inch of each case 15 fits loosely within the upper half inch of the cavity 24 of another case 15 disposed in vertical alignment therebeneath.

The skeleton 18 includes a rectangular perimetric top reinforcing frame 30 which is formed by the outward thickening of the upper edge portions of side walls 21 and end walls 22.

The skeleton 18 also includes a rectangular perimetric bottom reinforcing frame 31 which is formed by extending lower edge portions of side walls 21 and end walls 22 below the bottom 19 by an amount equal to several times the thickness of said bottom, and by the inward thickening of the lower edge portions of the side walls 21 and end walls 22 by an amount equal to several times the thickness of said side walls. Frame 31 is integral with the bottom 19 and thus has the additional aspect of constituting a downward thickening of perimetric portions of the bottom 19 several times the thickness of said bottom.

To reinforce the thin side and end Walls of shell 17 and provide rests for limiting the distance the bottom portion of each. case may be inserted downwardly into the cavity 24 of a case therebelow, the skeleton 18 also 3 includes upright pilaster-like, downwardly tapering, corner reinforcing element 32 andintermed.iate side wallreififorcing elements 33.

; Cornerreinforcing elements 32, areuformed by downwardly thickening top frame 30"and outwardly, thickening 'adjacent edges of side,walls 21fandjendfwallsh22, and 'extenddownward to terminate one ,halfjnch abpvebottorn surfaceZS of the case 15. i

The lower extremities of 'upright reinforcing; elements 32'and 33 at least patrially overlap and are, integral ,with rectangularperimetric bottom reinforcingfrarne 31. The skeleton 18 is thus seen to be formedby; 9, integral union of the perimetrictop and bottomreinforeing frames 30 and 3,1 with opposite, ends of jthe, upright, reinforcing elements 32 and 33, as, wellas al1- of these skeleton elementsbeing integral withthe, adjacent; walls of, the shell 17. Skeleton 18' comprises, six rectangular pcrimetric reinforcingframes including two .rectangular endlframes, two rectangular side frames,and rectangulartop, and bottom frames 30 and 31. The, skeleton side frames are reinforced, and divided into equalrectangles by, the: intermediate reinforcing elements 33.

As shown by thebottomplan view. QfFigarS, them;- right reinforcing elements 32 and, 33 are tapered, downwardly so as to readily draw from the female halffof the mold. This taper is accomplished while leaving substantial'abutting faces on the lower extremities of elements 32-and 33 which faces lie in thesame, horizontal plane and simultaneously engage thetop surface 16 of a case 15 disposed in nesting relation therebeneath as shown in Figs. and 11'.

Furthermore, the uprightelements 32 and 33 of successive cases thus stacked are thereby placed in vertical end to-end' abutment causing, these to form upright compressionrnembers extending from the bottom tothe-top of the stack. This concentrates thestressesof supportingthe upper cases in a stack, in these vertical compres sion members which areheavily const-ructed. with special reference to makingthem able, tosustain these loads with an ample margin of strength. The. lighter structure of cases 15Jat the lower end offstack are thus freed, from undue stresses which might otherwise be, imposed by the \vcightof loaded cases resting thereon,

The hand holes 23 are locatedinstheend walls 22, just beneath the rectangular perimetric top reinforcing frame 30 so that end portions of this framemay be, gripped in the hands, when the fingers are extendedinward through said holes.

The rectangular perimetric, bottom reinforcingframe 31 of the skeleton 18 includes side members 40 and end members 41', the latter being of substantially wider and heavier construction than the members 40.to, withstand strains imposed by conveyor lugs engaging members 41 in propelling the cases 151 along a conveyora Power conveyors for handling milk casesv gnerally include a pair of tracks or chains so, closely spaced as tosupport'cases 15 entirely bycontact of the crossmemhers 41' with the conveyor. The substantial longitudinal molded of'apolyester resin under high pressurewith fiber i glass reinforcing material packed in, the-mold and thus embedded'in the plastic forming the various elements. of the case, when the latter is taken from themold.

It is believed manifest from the foregoingdescription and the accompanying'drawings' that the present inveni tion provides a plasticcase of greatstrengt-h' for its weight, which has.relatively low-tooling and production costs, and

which provides a novel and highly effective means for nesting the cases when stacked without requiring any lugs projecting above or below the body of the case.

The claims are:

1. In an integrally molded plastic case, the combination of: a thin shell comprisinga bottom, side walls and end walls, said side and end walls converging slightly from top? totbottomrtmpermit withdrawalvof, said case upwardly fromthe mold in which it is formed and to permit a lower end, portion of said shell of one of said cases.to tit, withinan;upperl end portion ofv the, shell of another; of said,casestherebelow;a perimetric top -reinforcingframe formed by outwardly thickening upper edge portions of-said side and end walls; a perimetricbottom reinforcing frameforrned by extendingdower edge portions of said side and end walls several times the thickness of said bottom below said bottom and inwardly thickening said lower edge portions of said side and end walls several times. the thickness ofsaid side i and end walls,- said bottom-reinforcingframe constituting a downward 'thiekening of perimetric portions of said shellrbottom several times the thickness of said bottom; and a series of 'downwardlytapering upright wall reinforcing elements-formed by outwardly thickening said shell walls, said upright' elements also constituting the downwardly tapering, downward thickening of said top reinforcing frame-at spaced points about said case with the lower ends-of said npr-ight elements terminating short distances above the loweredges ofsaid shell Walls by at least partially overlapping with said perimetric bottom reinforcing frame, whereby said-upright elements ofone case rest on the top-perimetric reinforcing frame of a case disposed therebelowirr nesting relation therewith, said tapering upright reinforcing elements beinglocated at the vertical cor-ner edges of said shell whereby said elements reinforcesaid sideand end walls at their'lines of juncture and unite-withsaid top and bottom perimetric reinforcing-framesto-form an integral skeleton of six rectangular frames, five=of-which are reinforced in the planes of said rectangular frames by said ends, sides and bottom of said shell.

2; A combination as in claim 1 in which tapering uprightreinforcing elementsare also provided at mid points in said shell side walls, said middle side reinforcing elements dividing each of the side rectangular frames into two rectangular f-ramesections integrally united within said skeleton,

3-; Inan integrally molded plastic case, the combination of: a thin shell comprising a bottom, side walls and end walls said side and end walls converging slightly from top'to, bottom to permit withdrawal of said case upwardlyfrom the mold in which it is formed and to permit a, lower end portion of said shell of one of said cases to fit'within an upper end portion of the shell of another of said cases disposed therebelow; a rectangular perimetric top reinforcing frame formed by outwardly thickening upper edge portions of said side and end walls; a rectangularperimetric bottom reinforcing frame formed by extending lower edge portions of said side and end walls below said bottom several times the thickness of said bottom, and inwardly thickening said lower edge portions of said side and end walls several times the thickness; of said walls, said bottom reinforcing frame constituting a downward thickening of perimetric portions of said shell'bottom, several times the thickness of said bottom; and a series of downwardly tapering upright wall reinforcing elements formed by outwardly thickening said shell side and end walls, said upright elements also constituting a downward thickening of said top reinforcing frame at the corners of said shell, said upright elements thereby reinforcing said side and end walls at their lines of'juncture and extending downwardly in overlapping relation with at least a portion of said perimetric bottom reinforcing frame and being integrally united at their opposite ends with said top and bottom reinforc- References Cited in the file of this patent UNITED STATES PATENTS Marsden June 1, 1926 Runyan Dec. 5, 1933 Nicholson Dec. 20, 1938 Bartholomew Apr. 7, 1953 

